How secure is the hardware that we use? With recent NSA revelations - question rises - do we have these already embedded into popular hardware?
Hardware Trojans are created with intentional and malicious changes to hardware's initial design. And are almost impossible to detect.
The demonstration below from DEFCON-16 shows
Thermal trojan - Exposes data via thermal emission
Optical - Invisible data transmissions via the regular Power-LED
Radio - Additional pins causing radio emission.